Colourant composition for paint products

Abstract

The invention relates to colorants (colorant pastes) used for the tinting of paint products. The colorants contain: 2-75 wt-% (A) pigment component comprising of one or more organic and/or inorganic pigments and possibly extender pigments, 10-60 wt-% (B) diluent component comprising of one or more organic solvents other than aliphatic alcohols or aromatic hydrocarbons, wherein 20-100% of the total weight of the diluent consists of a biodegradable ester of lactic acid and an alcohol, preferably ethyl or isopropyl lactate, 10-50 wt-% (C) binder component (calculated as 100% non-volatile matter) comprising one or more binders soluble in the diluent (B), wherein 70-100% of the total weight of the binder consists of a ketone aldehyde, ketone and/or aldehyde resin soluble in aliphatic hydrocarbons and 0-30% of the total weight of the binder consists of other binders commonly used in colorants, for example acrylic, alkyd or polyester resin, and 0-5 wt-% (D) additive component (calculated as 100% active matter) comprising one or more additives suitable for use in colorants. The binders and additives may be delivered undiluted (solvent-free) or they may contain as a diluent organic solvents that in the colorant are considered as a part of the diluent component (B). The present invention relates not only to the above mentioned colorants but also to their use as a part of a tinting system of solvent-borne paint products.

We claim: 
     
       1. A colourant composition for solvent-borne paint products comprising 2-75% by weight of a pigment component (A) consisting of one or more organic and/or inorganic pigments and possibly extender pigments, 10-60% by weight of a diluent component (B) consisting of one or more organic solvents not being an aliphatic alcohol or aromatic hydrocarbon, 10-50% by weight with respect to the total weight of components A, B, C, and D, of a binder component (C) consisting of one or more binders soluble in the diluent component (B), and 0-5% by weight with respect to the total weight of components A, B, C, and D, of an additive component (D) consisting of one or more additives suitable for use in colourants, wherein 20-100% of the total weight of the diluent component (B) consists of a biodegradable ester of lactic acid and a C 1  -C 10  -alcohol and 70-100% of the total weight of the binder component (C) consists of a ketone aldehyde resin, ketone resin and/or aldehyde resin at least partially soluble in paint solvents including aliphatic hydrocarbons. 
     
     
       2. A colourant according to claim 1, wherein 20-50% by weight with respect to the total weight of the diluent component (B) consists of a biodegradable ester of lactic acid and C 1  -C 10  alcohol. 
     
     
       3. A colourant according to claim 1, wherein the biodegradable ester of lactic acid and C 1  -C 10  alcohol of the diluent component (B) is an ester which is a lactate of the following general formula   CH.sub.3 --CH(OH)--CO--OR     where R is a C 1  -C 4  -alkyl group.   
     
     
       4. A colourant according to claim 3, wherein the biodegradable ester of lactic acid and C 1  -C 4  alcohol of the diluent component (B) is an ethyl lactate or an isopropyl lactate. 
     
     
       5. A colourant according to claim 1, wherein 0-80% by weight, with respect to the weight of the diluent component (B), consists of a C 1  -C 4  alkyl ether or a C 1  -C 4  alkyl ether ester of ethylene glycol or propylene glycol. 
     
     
       6. A colourant according to claim 1, wherein 80-100% by weight with respect to the total weight of the binder component (C) consists of a ketone aldehyde resin, ketone resin and/or aldehyde resin also soluble in aliphatic hydrocarbons. 
     
     
       7. A colourant according to claim 1, wherein the mentioned ketone aldehyde resin, ketone resin and/or aldehyde resin of the binder component (C) is a resin with a softening point between 65 and 90° C. 
     
     
       8. A colourant according to claim 1, wherein the mentioned ketone aldehyde resin, ketone resin and/or aldehyde resin of the binder component (C) is a resin with a number-average molecular mass M n  in the range of 500-3000 g/mol. 
     
     
       9. A colourant according to claim 1, wherein the mentioned ketone aldehyde resin of the binder component (C) is a resin produced by an aldol polycondensation of non-cyclic or cyclic aliphatic ketones and aliphatic aldehydes. 
     
     
       10. A colourant according to claim 1, wherein the mentioned ketone resin soluble in aliphatic hydrocarbons of the binder component (C) is a resin produced by an aldol condensation of non-cyclic or cyclic aliphatic ketones. 
     
     
       11. A colourant according to claim 1, wherein the mentioned aldehyde resin soluble in aliphatic hydrocarbons of the binder component (C) is a resin produced by cyclo- or polycondensation reaction of urea and an aliphatic aldehyde. 
     
     
       12. A colourant according to claim 1, wherein 0-30% by weight, preferably 0-20% by weight, with respect to the total weight of the binder component (C) consists of a thermoplastic acrylic resin. 
     
     
       13. A colourant according to claim 1, wherein the pigment component (A) consists of one or more organic pigments selected from the following pigment groups: azo pigments, metal-complex pigments, isoindolinone and isoindoline pigments, phthalocyanine pigments, quinacridone pigments, perinone and perylene pigments, anthraquinone pigments, diketopyrrolopyrrole pigments, dioxazine pigments, quinophthalone pigments and fluorescent pigments. 
     
     
       14. A colourant according to claim 1, wherein the pigment component (A) consists of one or more inorganic pigments selected from the following pigment groups: elementary pigments, oxide and oxide hydroxide pigments, oxide mixed-phase pigments, sulphide and sulphate pigments, chromate and chromate molybdate mixed-phase pigments, complex salt pigments and silicate pigments. 
     
     
       15. A colourant according to claim 1, wherein the additive component (D) consists of one or more additives suitable for use in colourants selected from non-ionic dispersing agents, anionic dispersing agents, ampholytic dispersing agents and/or polymeric dispersing agents. 
     
     
       16. A colourant according to claim 1, wherein the additive component (D) consists of one or more rheology additives suitable for use in colourants. 
     
     
       17. A solvent-borne, including white spirit containing, paint product or a paint product having a high solids content (so-called HS-paints) containing the colourant of claim 1. 
     
     
       18. The colourant of claim 5 wherein 50-80% by weight, with respect to the weight of the diluent component (B), consists of a C 1  -C 4  alkyl ether or C 1  -C 4  alkyl ether ester of ethylene glycol or propylene glycol. 
     
     
       19. The colourant of claim 5 wherein the C 1  -C 4  alkyl ether or C 1  -C 4  alkyl ether ester of ethylene glycol or propylene glycol is selected from the group consisting of propylene glycol monomethyl ether, propylene glycol mono n-butyl ether, propylene glycol monomethyl ether acetate, and dipropylene glycol dimethyl ether. 
     
     
       20. The colourant of claim 5 wherein the C 1  -C 4  alkyl ether or C 1  -C 4  alkyl ether ester of ethylene glycol or propylene glycol is propylene glycol mono n-butyl ether acetate.